Fried snack pieces and process for preparing

ABSTRACT

A process for preparing reduced fat shaped snack products having a light, crispy, crunchy texture is disclosed. A sheetable dough comprising: 
     (1) from about 50% to about 70% of a source of starch based flour comprising a mixture of for about 75% to about 90% of a flour having a WAI of from about 7 to about 9 and from about 10% to about 25% of a flour or starch having a WAI of from about 4 to about 6; 
     (2) at least about 3% hydrolyzed starches having a DE of from about 5 to about 30; 
     (3) from about 0% to about 6% of an emulsifier; 
     (4) from about 20% to about 40% added water; 
     (5) from about 1% to about 4% triglyceride, reduced calorie fat or a polyol fatty acid polyester; and 
     (6) from 0 to about 3% solute is formed. 
     The dough is sheeted and the sheet is cut into snack pieces. The snack pieces are fried to provide a snack having 20% to 32% fat.

This is a continuation of application Ser. No. 08/644,766, filed May 10, 1996, now abandoned.

TECHNICAL FIELD

This application relates to an improved fried snack product which is generally lower in fat than other fried snacks. In particular, this application relates to a process for preparing such products from a dough containing specific starches and hydrolyzed starches, e.g. maltodextrin or corn syrup solids (D.E. of 5 to 30) and relatively low levels of water, and optionally a polyglycerol ester emulsifier or other emulsifier which can be dissolved in triglyceride, reduced calorie fat or a polyol fatty acid polyester.

BACKGROUND OF THE INVENTION

A wide variety of starch and protein-based snack food products are presently available to the consumer. Many of these products are in the form of chips, strips, and extruded tubular pieces. Some of these products are expanded or puffed and contain a cellular or honeycombed internal structure. In addition, most of the present-day snack products contain a fairly high level of fat, either in the form of separately added ingredients, such as cheese, or in the form of fats imparted to the product during cooking, as in the case of corn or potato chips. Fat improves the flavor and palatability of these products. However, it also increases the caloric value of the product. Even chips and snacks fried in non-digestible fats such as olestra, contain some fat in the form of emulsifiers or oils or fats naturally present in the grains used to make the product.

Accordingly, it would be desirable to provide reduced fat snack products which have an attractive appearance, texture and taste.

There have been several attempts at lowering the fat content of potato chips and of potato snacks made from doughs. One method involved coating chips with an aqueous dispersion of a high amylose starch. This is said to produce a potato chip with minimal oil pick-up and low variation in the amount of oil absorbed. (see RE 27,531 of U.S. Pat. No. 3,597,227 issued to Muray, et al., 1971). Coating of breaded or batter food products with a film forming agent such as gelatin or starches is also said to lower oil absorption by the foods when they are fried (U.S. Pat. No. 4,511,583 issued to Olson, et al, 1985). U.S. Pat. No. 5,085,884 issued to Young et al, describes reduced calorie potato chips which are made with nondigestible fats, in particular with polyol fatty acid polyesters. However, when making fabricated snacks, those made from doughs, other considerations arise. For example, the dough has to be sheeted or extruded. Low water doughs produce lower fat products but they are also harder doughs to sheet and handle. U.S. Pat. No. 5,464,643 (issued to Lodge, 1995) describes the use of hydrolyzed starches as part of the dough to provide snacks with a lower fat content.

Since the solids content, degree of hydrolysis and the water content of the dough also affect the browning and the texture of the product, a way to control these parameters is also needed.

It is therefore an object of this invention to make a fried snack containing a fat or oil including nondigestible oil which is lower in fat content than other fabricated snacks yet has good flavor and texture.

It is a further object of this invention to make a fried potato snack which produces a uniform product in a controlled process.

DISCLOSURE OF THE INVENTION

The present invention relates to an improved reduced fat fried snack product and a process for it.

This process comprises the steps of:

(a) forming a sheetable dough comprising:

(1) from about 50% to about 70% of a source of starch based flour comprising a mixture of from about 75% to about 90% of a flour having a WAI of from about 7 to about 9 and from about 10% to about 25% of a flour or starch having a WAI of from about 4 to about 6;

(2) at least about 3% hydrolyzed starches having a DE of from about 5 to about 30;

(3) from about 0% to about 6% of an emulsifier;

(4) from about 20% to about 40% added water;

(5) from about 0% to about 6% triglyceride, reduced calorie fat or a polyol fatty acid polyester; and

(6) from 0% to about 3% solutes;

(b) forming the dough into a sheet;

(c) cutting snack pieces from the sheet; and

(d) frying said snack pieces in a fat or oil.

The snack pieces are fried at a temperature sufficient to form snack products having a light, crispy, crunchy texture, improved flavor and a fat content of from about 20% to about 38%.

A particularly important aspect of the process of the present invention is the mixture of the flours having the different Water Absorption Indices (WAI). This dough formulation allows ready transport of water during frying thus allowing finer bubble nucleation with early product expansion during frying leading to the creation of small void spaces contributing to a crisper texture. This is particularly true for oils which are more viscous as nondigestible fats can be.

All percentages and proportions are "by weight" unless otherwise specified.

A. Dough Formation

A particularly important aspect of the process of the present invention is the dough. This dough is formed from a combination of starch based flour, water, hydrolyzed starches, an emulsifier, a fat or polyol fatty acid polyester, as well as other optional ingredients to be described hereinafter. The composition of this dough has two significant effects. One relates to the ability to process the dough into a sheet from which snack pieces of predetermined shape and size are subsequently formed. These dough pieces are then fried to form thin, crisp, shaped snack products. The other effect of the dough composition relates to the textural and flavor features of the resulting fried snack product. Snack products prepared according to the process of the present invention have a relatively light, crunchy texture.

As used herein, the term "crunchy texture" refers to a snack that exhibits a crisp and crunching sensation for the first of several chews.

An important component of this dough is a starch based flour. The dough preferably comprises, by weight, about 55% to about 65%, starch based flour. Potato flour is the most preferred source of starch based flour. Suitable sources of potato flour include, dehydrated potato flakes and granules, mashed potato materials, and dried potato products. Other tuber and grain flours such as tapioca, peanut, wheat, oat, rice, corn flour, corn meal and soy meal can be used in the dough. These starch based flours can be blended to make snacks of different composition and flavor. Suitable starches can be used in combination with the potato flour. Examples of such materials are potato starch, tapioca starch, cornstarch, oat starch, rice starch and wheat starch. Most preferably these starches are cooked so the starch has gelatinized and then are dried and milled to make a flour. These starches are called pregelatinized starches. For example, potato flour is at least 90% pregelatinized starch. Preferred flours contain at least 80% pregelatinized starch. Potato flakes generally contain more pregelatinized starch than potato granules. A preferred combination is 80:20 to 95:5 potato flakes to potato granules. It is understood that other sources of pregelatinized starches other than potato flakes and potato granules can be used.

The Water Absorption Index (WAI) of the carbohydrate or starch component is important for controlling the starch hydration. Preferably the potato flour material which is used as the predominant potato ingredient has a WAI of between 7 and 9 and that of the other starch ingredient has a WAI of between 4 and 6.

When the starches have very different WAIs or are mixed in different ratios, the compositions have slower initial moisture evolution that case hardens the dough surface prior to expansion during frying. When expansion does occur with the case hardened surface, it promotes moisture bubble coalescence due to increased diffusional resistance. Larger void spaces result between thicker layers of chip mass in the final product. The chip mass layers consist of carbohydrate materials surrounded by frying oil. Due to the slower evolution of moisture during frying, the chip mass layers are able to swell, becoming larger than typical and they become less fully cooked due to this larger volume to surface area ratio. The end result is a less crisp product due to a lower degree of cooking for the bulk chip mass phase and lower internal void volume.

It was found in this composition that the dough carbohydrate and water phase composition play a large role in governing the final fried chip texture. Controlling the rheology of the dough by limiting potato flake hydration is critical. This first was accomplished by adding materials with a more similar WAI that could compete for available water and retain their native structure with less swelling due to their precooked nature. The second method of controlling the rheology is to add ingredients to the dough formulation water that would act like a humectant system that would improve water coating properties with less hydration, they are referred to as "solutes".

Solutes can be present from 0% to about 3% of the dough, preferably from about 1% to about 2.5%, more preferably from about 0.5% to about 2%. Preferred solutes are salt and sugars, e.g., sodium chloride, potassium chloride, mixtures of sodium and potassium chloride, sucrose, maltose, dextrose and fructose. It has been found that the addition of sucrose and salt at levels of about 0.5 to about 1.5% of the dough will improve the dough rheology. They also improve the flavor.

Salt, flavorings, and/or seasonings can also be included in the dough or sprinkled on the surface of the snack after frying.

Hydrolyzed starches are also a key ingredient for the processability of the doughs of the present invention which have relatively low water levels. In the absence of hydrolyzed starches, low moisture levels in the dough can prevent formation of a continuous, smooth extensible dough sheet and can hinder subsequent expansion of the dough pieces during frying, even if the dough can be sheeted. It also affects the elasticity of the dough. In addition, low moisture doughs tend to produce a harder and more brittle texture in the resulting snack products.

As used herein, the term "hydrolyzed starches" refers to oligosaccharide-type materials that are typically obtained by acid or enzymatic hydrolysis of starches, preferably corn starch. Suitable hydrolyzed starches for inclusion in the dough include maltodextrins and corn syrup solids. The hydrolyzed starches for inclusion in the dough have Dextrose Equivalent (D.E.) values of from about 5 to about 30, preferably from 0 about 10 to about 20. Maltrin™ M050, M100, M150, M180, M200, and M250 (available from Grain Processing Corporation, Iowa) are preferred maltodextrins. The D.E. value is a measure of the reducing equivalence of the hydrolyzed starch referenced to dextrose and expressed as a percent (on a dry basis). The higher the D.E. value, the more reducing sugars are present.

Hydrolyzed starches are included in the dough in an amount of at least about 3%, with a usual range of from about 3% to about 15%. Preferably, hydrolyzed starches are included in an amount of from about 5% to about 12%.

As previously alluded to, another important characteristic of the dough of the present invention is its water content. As used herein, the term "added" refers to water which has been added to the dry dough ingredients. Water which is inherently present in the dry dough ingredients, such as in the case of the sources of flour and starches, is not included in the added water. The level of water in flours and starches is usually from about 3% to about 8%. However, if the maltodextrin or corn syrup solids are added as a solution or syrup, the water in this syrup or solution must be accounted for as "added water".

The doughs of the present invention can comprise from about 20% to about 40% added water. Preferably, these doughs comprise from about 23% to about 35%, more preferably at least about 25% to about 35%, added water. This low level of water in the dough along with the addition of hydrolyzed starches to the doughs provides doughs which can form cohesive sheets. In addition, the low moisture level of the doughs of the present invention are important in reducing the oil content of the final fried snack pieces.

Emulsifiers can be added in amounts up to about 6% by weight, preferably from about 0.5% to about 5%, and most preferably from about 1% to about 3%. Emulsifiers are used as a sheeting aid to avoid overworked sticky doughs and to reduce puffing and blistering in the fried product. Lower moisture doughs, when fried, typically yield harder snack products. To make products with textures similar to those made from higher moisture doughs, the level of emulsifier is typically reduced.

The emulsifier is selected from the group consisting of polyglycerol monoesters, mono and diglycerides of fatty acids and diacetyl tartaric acid monoglycerides. It is preferably added to the dough in a fat or oil.

The diacetyl tartaric acid monoglyceride is a fatty acid ester of glycerine which is esterified with diacetyl tartaric acid and a fatty acid having from 12 to about 22 carbon atoms. The fatty acid may be saturated or unsaturated. The Iodine Value of the diacetyl tartaric acid monoglyceride is from about 50 to about 110. Preferably, the IV is from about 70 to about 85. The diacetyl tartaric acid monoglyceride is really a mixture of monoglycerides and diglycerides. A preferred source of these materials is the Panodan SD emulsifiers sold by Danisco, Kansas City USA. This is the most preferred emulsifier.

Polyglycerol esters of lower molecular weight can be used herein. These are predominantly polyglycerols which are diglycerol or triglycerol entities. Any time glycerine is polymerized a mixture of polyglycerols are formed. Most preferred for use in this invention is a diglycerol monoester which is a mixture of monoesters of polyglycerol which is predominantly a diglycerol. The preferred fatty acids used to made the esters are saturated and unsaturated fatty acids having from 12 to 22 carbon atoms. The most preferred diglycerol monoester is diglycerol monopalmitate.

Preferred polyglycerol emulsifiers are monoesters of polyglycerols, preferably hexapolyglycerols. The average number of glycerol units is not an exact number. It should be understood that a hexapolyglycerol will contain some tri-, tetra-, penta-, hepta- and octapolyglycerol units. The preferred polyglycerol fatty acid monoesters can be characterized by the average hydroxyl value (number of free or unesterified hydroxy groups, the saponification value which measures the number of ester groups) the percent monoester, the palmitic to stearic acid ratio, and the complete melting point.

The polyglycerol esters can be defined as having a complete melt point of between about 121° F. (49° C.) and about 147° F. (64° C.) preferably between about 121° F. (49° C.) and about 131° F. (55° C.); an onset of crystallization temperature of between about 110° F. (43° C.) and about 120° F. (49° C.); preferably between about 114° F. (46° C.) and about 118° F. (48° C.); a saponification value of between about 80 and about 135, preferably between 95 and 120; a hydroxy value of between 300 and 575; preferably between 400 and 475; and a palmitic to stearic acid ratio of between 2:1 and 5:1. The percent monoester is at least 40% and preferably between about 45 and about 55%.

In addition to the stearic and palmitic fatty acids, unsaturated fatty acids having from 14 to 20 carbon atoms can be present as can saturated fatty acids having 16 to 22 carbon atoms. The fatty acid ester group is mostly stearic and palmitic acids (about 75% or more).

Mono and diglycerides saturated and unsaturated fatty acids having from 12 to 22 carbon atoms can also be used herein.

As used herein, "fat or oil" includes triglycerides, animal, marine or vegetable oils which can be partially or fully hydrogenated; nondigestible fats or oils and reduced calorie fats and oils.

The terms "fat" and "oil" are used interchangeably unless otherwise specified.

The dough also contains a liquid oil, shortening or solid fat, preferably a shortening is used. A shortening contains both liquid and solid fats. Usually from about 80% to 95% of a liquid oil is used and from about 5% to about 20% of a solid fat is used. The dough generally comprises, by weight, from about 0% to about 6%, preferably from about 1% to about 4% of a fat; the fat is preferably selected from the group consisting of triglyceride, reduced calorie fat, polyol fatty acid polyester and mixtures thereof. The preferred sources of the oil and fat are vegetable oils such as partially hydrogenated canola oil, corn oil, soybean oil, rapeseed oil, peanut oil or cottonseed oil. Animal fats or marine oils may also be used. The preferred shortenings are beta prime shortenings.

Both nondigestible and digestible fats can be used. Nondigestible fats such as polyol polyesters, and reduced calorie fats such as those made with long chain and medium or short chain fatty acids can also be used. See for example, U.S. Pat. No. 4,005,195 and U.S. Pat. No. 4,005,196 issued to Jandacek et al.; U.S. Pat. No. 4,832,975 issued to Yang, U.S. Pat. No. 4,582,715 issued to Volpenhein, U.S. Pat. No. 5,419,925 issued to Seiden et al., U.S. Pat. No. 5,288,512 issued to Seiden; U.S. Pat. No. 5,422,131 issued to Elsen et al., and U.S. Pat. No. 4,861,613 issued to White and preferably, U.S. Pat. No. 5,085,884 issued to Young et al., 1992.

The emulsifier is preferably dissolved in a polyol fatty acid polyester, preferably a sucrose fatty acid ester such as olestra. The emulsifier comprises from about 10% to about 30% of the fat composition which is added. Preferably the composition contains about 25% emulsifier and 75% sucrose fatty acid polyester. Other fats and oils can also be used in these combinations.

The dough of the present invention can be prepared by any suitable method for combining the previously described ingredients. Typically, a loose, dry dough is prepared by thoroughly mixing together the flours and/or starches and optionally an emulsifier and sucrose polyester combination. A water preblend of flavoring (optional), hydrolyzed starches, sucrose and/or salt are separately mixed to obtain the previously defined hydrolyzed starch and water levels. The water preblend is then added to the flour and emulsifier blend. Preferred devices for mixing together these dough ingredients are conventional mixers. Hobart® mixers are used for batch operations and Turbolizer® mixers can be used for continuous mixing operations. However, extruders can also be used to mix the dough and to form the sheets or shaped pieces.

The capability of the emulsifier to mix thoroughly with the other ingredients and to readily disperse throughout the dough during mixing and milling are very important. It was found that certain chemical and physical properties correlate to the successful use of emulsifiers and anti-sticking, sheeting and processing aids.

B. Sheeting, Snack Piece Formation and Frying

Once prepared, the dough is then formed into a relatively flat, thin sheet. Any method suitable for forming such sheets from starch based doughs can be used. For example, the sheet can be rolled out between two counter rotating cylindrical rollers to obtain a uniform, relatively thin sheet of dough material. Any conventional sheeting, milling and gauging equipment can be used. It has been found however, that the mill rolls should be heated to about 90° F. (32° C.) to about 135° F. (57° C.) to keep the emulsifier/sucrose polyester blend from congealing on the roll mills. In a preferred embodiment, the mill rolls are kept at two different temperatures, with the front roller being cooler than the back roller.

Doughs of the present invention are usually formed into a sheet having a thickness of from about 0.015 to about 0.10 inches (from about 0.038 to about 0.25 cm), and preferably to a thickness of from about 0.05 to about 0.10 inches (from about 0.013 to about 0.025 cm) and most preferably from about 0.065 in to about 0.08 in (1.65 to 2.03 mm). For rippled chips the most preferred thickness is about 0.75 in or 1.9 mm. The dough sheet is then formed into snack pieces of a predetermined size and shape. These snack pieces can be formed using any suitable stamping or cutting equipment. The snack pieces can be formed into a variety of shapes. For example, the snack pieces can be in the shape of ovals, squares, circles, a bowtie, a star wheel, or a pin wheel. The pieces can be scored to make rippled chips as described in Dawes, et al., WO 95/07610, Jan. 25, 1996.

The snack pieces are fried. Preferably the snacks are prepared by a continuous frying method and are constrained during frying. An apparatus as described in U.S. Pat. No. 3,626,466 (Liepa, 1971) can be used. The dough pieces are cut from the sheet, shaped using a movable, apertured mold half to shape the cut dough pieces and then held during subsequent frying by a second apertured mold half. A reservoir containing a frying medium is used. The shaped, constrained pieces are passed through the frying medium until they are fried to a crisp state with a final moisture content of about 0.5% to about 4% water.

Continuous frying or batch frying of the snack pieces in a non-constrained mode is also acceptable. In this method the pieces are immersed in the oil on a moving belt or basket.

If desired, the snack pieces can be fried to moisture contents of 10% or less and then heated with hot air, superheated steam or inert gas to lower the moisture level to 4% or less. This is a combined frying/baking step.

The frying medium comprises nondigestible fats and oils, triglycerides and reduced calorie fats.

Typical frying medium include fats and oils derived from animal and vegetable sources. Any hydrogenated or unhydrogenated fat can be used. These include corn oil, soybean oil, palm oil, cottonseed oil, canola oil, rapeseed oil, sunflower seed oil, lard, tallow, peanut oil, among others. Synthetic triglycerides can also be used, including low calorie or zero calorie fats, e.g. polyol polyesters of fatty acids such as sucrose polyesters, etc. The snack pieces are fried at temperatures between about 300° F. (148° C.) and 450° F. (232° C.). The exact fry time is controlled by the temperature of the oil and the starting water content. The fry time and temperature is easily determined by one skilled in the art.

Fat or oil refers to any edible fatty substances in a general sense; e. g., 100% natural or 100% synthetic fats and oils, unless otherwise specified. Preferred oils consist essentially of triglycerides, such as, for example soybean oil, corn oil, cottonseed oil, sunflower oil, palm oil, coconut oil, fish oil, and edible animal oil such as tallow. These oils can be partially or completely hydrogenated or modified by interesterification. The terms "fat" or "oil" also refer 100% non-toxic fatty materials having properties similar to triglycerides. The terms "fat" or "oil" in general include fat-substitutes, which materials may be partially or fully nondigestible.

The term "fat substitute" refers to those edible fatty materials that are partially or totally nondigestible, e.g., polyol fatty acid polyesters, such as olestra.

The fats used herein are selected from the group consisting of triglycerides, non-digestible fats or reduced calorie fats and mixtures thereof. Preferred triglycerides include soybean oil, corn oil, cottonseed oil, sunflower oil, palm oil, coconut oil, canola oil, fish oil, tallow, peanut oil, medium chain triglycerides, structured triglycerides containing a combination of short or medium chain fatty acids and long chain fatty acids (e.g. Caprenin-like) and the like which may have been partially or completely hydrogenated or otherwise modified. Non-toxic fatty materials having properties similar to triglycerides, herein referred to as fat substitutes can be partially or fully indigestible. Reduced calorie fats and edible non-digestible fats, oils or fat substitutes can also be used.

A variety of edible fats and oils may be used in the dough or to fry the snacks. Edible fats and oils suitable for use include but are not limited to those listed above. If desired the oils may be conditioned or flavored, see Flavored Vegetable Oils as a Substitute for Beef Tallow in Deep Frying Applications, Food Technology, pp. 90-94 (1989) and U.S. Pat. No. 5,104,678 (Yang et al.).

The oil may be partially or completely hydrogenated or modified otherwise. The preferred fat substitute are fatty materials having properties similar to triglycerides such as sucrose polyesters. OLEAN™, a preferred fat substitute, made by The Procter and Gamble Company. Reduced calorie fats, polyol fatty acid polyesters, and diversely esterified polyol polyesters or combinations of regular fats and fat substitutes can also be used herein. These preferred nondigestible fat or oil substitute compositions are described in the literature, for example, in Young, et al., U.S. Pat. No. 5,085,884, issued Feb. 4, 1992, and U.S. Pat. No. 5,422,131, issued Jun. 6, 1995 to Elsen et al.

One reduced calorie fat that has been found to be useful comprises a fairly high level (e.g., at least about 85%) of combined MML and MLM triglycerides, where M is typically a mixture of C₈ -C₁₀ saturated fatty acids and L is predominantly behenic acid, but can be C₂₀ -C₂₄. See U.S. Pat. No. 4,888,196 to Ehrman et al., issued Dec. 9, 1989 and U.S. Pat. No. 5,288,512 issued to Seiden, Feb. 22, 1994 for the synthesis and more detailed description of these reduced calorie fats.

By "polyol" is meant a polyhydric alcohol containing at least 4, preferably from 4 to 11 hydroxyl groups. Polyols include sugars (i.e., monosaccharides, disaccharides, and trisaccharides), sugar alcohols, other sugar derivatives (i.e., alkyl glucosides), polyglycerols such as diglycerol and triglycerol, pentaerythritol and polyvinyl alcohols. Specific examples of suitable sugars, sugar alcohols and sugar derivatives include xylose, arabinose, ribose, xylitol, erythritol, glucose, methyl glucoside, mannose, galactose, fructose, sorbitol, maltose, lactose, sucrose, raffinose, maltotriose and sorbitan.

By "polyol fatty acid polyester" is meant a polyol having at least 4 fatty acid ester groups. Polyol fatty acid esters that contain 3 or less fatty acid ester groups are generally digested in, and the products of digestion are absorbed from, the intestinal tract much in the manner of ordinary triglyceride fats or oils, whereas those polyol fatty acid esters containing 4 or more fatty acid ester groups are substantially non-digestible and consequently non-absorbable by the human body. It is not necessary that all of the hydroxyl groups of the polyol be esterified, but it is preferable that disaccharide molecules contain no more than 3 unesterified hydroxyl groups for the purpose of being non-digestible. Typically, substantially all, e.g., at least about 85%, of the hydroxyl groups of the polyol are esterified. In the case of sucrose polyesters, typically from about 7 to 8 of the hydroxyl groups of the polyol are esterified.

The polyol fatty acid esters typically contain fatty acid radicals typically having at least 4 carbon atoms and up to 26 carbon atoms. These fatty acid radicals can be derived from naturally occurring or synthetic fatty acids. The fatty acid radicals can be saturated or unsaturated, including positional or geometric isomers, e.g., cis- or trans- isomers, and can be the same for all ester groups, or can be mixtures of different fatty acids.

Liquid non-digestible oils have a complete melting point below about 37° C. include liquid polyol fatty acid polyesters (see Jandacek; U.S. Pat. No. 4,005,195; Issued Jan. 25, 1977); liquid esters of tricarballylic acids (see Hamm; U.S. Pat. No. 4,508,746; Issued Apr. 2, 1985); liquid diesters of dicarboxylic acids such as derivatives of malonic and succinic acid (see Fulcher, U.S. Pat. No. 4,582,927; Issued Apr. 15, 1986); liquid triglycerides of alpha-branched chain carboxylic acids (see Whyte: U.S. Pat. No. 3,579,548; Issued May 18, 1971); liquid ethers and ether esters containing the neopentyl moiety (see Minich; U.S. Pat. No. 2,962,419; Issued Nov. 29, 1960); liquid fatty polyethers of polyglycerol (See Hunter et al; U.S. Pat. No. 3,932,532; Issued Jan. 13, 1976); liquid alkyl glycoside fatty acid polyesters (see Meyer et al; U.S. Pat. No. 4,840,815; Issued Jun. 20, 1989); liquid polyesters of two ether linked hydroxypolycarboxylic acids (e.g., citric or isocitric acid) (see Huhn et al; U.S. Pat. No. 4,888,195; Issued Dec. 19, 1988); liquid esters of epoxide-extended polyols (see White et al; U.S. Pat. No. 4,861,613; Issued Aug. 29, 1989); liquid polydimethyl siloxanes (e.g., Fluid Silicones available from Dow Coming). Solid non-digestible fats or other solid materials can be added to the liquid non-digestible oils to prevent passive oil loss. Particularly preferred non-digestible fat compositions include those described in U.S. Pat. No. 5,490,995 issued to Corrigan, 1996. U.S. Pat. No. 5,480,667 issued to Corrigan et al, 1996, U.S. Pat. No. 5,451,416 issued to Johnston et al, 1995 and U.S. Pat. No. 5,422,131 issued to Elsen et al, 1995. U.S. Pat. No. 5,419,925 issued to Seiden et al, 1995 describes mixtures of reduced calorie triglycerides and polyol polyesters that can be used herein.

Other ingredients known in the art may also be added to the edible fats and oils, including antioxidants such as TBHQ, chelating agents such as citric acid, and anti-foaming agents such as dimethylpolysiloxane.

The snack pieces are fried at temperatures between about 300° F. (148° C.) and about 450° F. (232° C.). The exact fry time is controlled by the temperature of the oil and the starting water content. The fry time and temperature is easily determined by one skilled in the art.

The snack products made from this process typically have from about 20% to about 32% fat. Preferably, the fried snacks will have from about 23% to about 28% fat content. If a higher fat level is desired in the snack product to further improve the lubricity of the snack, oil can be sprayed onto the snack product when it emerges from the fryer, or when it is removed from the mold used in constrained frying. These include low calorie and nonabsorbable fats such as sucrose polyesters. Preferably the oils for spraying will have an iodine value greater than 75, and most preferably above 90. Oils with characteristic flavors or highly unsaturated oils can be sprayed on the snack product. Oils with added flavors can be used. These include butter flavored oils, natural or artificial flavored oils, herb oils and oils with garlic or onion flavors added. This is a way to introduce a variety of flavors without having the flavor undergo browning reactions during the frying. It also avoids adding the flavor to the dough and having the flavor react with or leach into the oil during the frying process. This method can be used to introduce healthier oils which would ordinarily undergo polymerization or oxidation during the heating necessary to fry the snacks.

Oil spray can be used to increase the oil content from the 22% to 38% fat content as the snack product emerges from the fryer to as high as 44% oil. Thus a snack product having from 30% to 44% can be made using this additional step.

ANALYTICAL METHODS

The hydroxyl value is determined by AOCS (American Oil Chemists Society) Method Cd 13-60 revised in 1989.

The Saponification Value is determined by AOCS method Cd 3-25 revised in 1989.

Complete Melting Point is determined by the Differential Scanning Method described at column 22, lines 6-35 of U.S. Pat. No. 5,085,884 issued to Young et al, Feb. 4, 1992, which method is incorporated herein by reference.

The onset of crystallization temperature is measured by Differential Scanning Calorimetry by cooling a melted sample. The onset of crystallization is the temperature at which the exothermic peak first begins.

"Water Absorbance Index" and "WAI" refers to the measurement of the water holding capacity of any carbohydrate based material as a result of a cooking process. (See for example Anderson, R. A., Conway, H. F., Pfeifer, V. F. and Griffin, Jr., E. L., 1969, Gelatinization of Corn Grits By Roll- and Extrusion-Cooking. CEREAL SCIENCE TODAY; 14(1):4). This measurement is typically expressed as the ratio of mass of water held per unit mass of material. The WAI for a sample is determined by the following procedure. The weight to two decimal places of an empty centrifuge tube is determined. Two grams of dry sample (e.g., potato flakes) are placed into the tube. Thirty mililiters of water is added to the tube. The water and sample are stirred vigorously to insure no dry lumps remain. The tube is placed in a 29° C. (85° F.) water bath for 30 min., repeating the stirring procedure at 10 and 20 min. The tube is then centrifuged for 15 min. at 3,000 RPM. The water is then decanted from the tube, leaving a gel behind. The tube and contents are weighed. The WAI is calculated by dividing the weight of the resulting gel by the weight of the dry sample (i.e., weight of tube and gel!- weight of tube!÷ weight of dry flakes!).

EXAMPLE 1

A mix consisting of approximately 61.2% potato flakes with a WAI of about 8 and 6.8% potato granules with a WAI of about 5.0 are blended with water, 27.6%, 3.8% Maltodextrin having a DE of about 18 available from Grain Products Corporation and sucrose (0.3%) and salt (0.3%) to form a loose, dry dough in a continuous Turbolizer® mixer with a residence time of 15 to 60 seconds.

The dough is sheeted by continuously feeding the dough through a pair of sheeting rolls forming an elastic continuous sheet without pin holes. Sheet thickness is controlled to 0.020 inches (0.05 cm). The front roll is heated to about 90° F. (32° C.) and the back roll is heated to about 135° F. (57° C.). The dough sheet is then cut into oval shaped pieces and fried in a constrained frying mold at 350° F. (177° C.) in OLEAN to dryness (about 12 seconds). The product is held in the molds for 20 seconds to allow the OLEAN to drain. The resulting product has a crisp, light texture with a fat level of about 32%. 

What is claimed is:
 1. A process comprising the steps of:(a) forming a sheetable dough comprising:(1) from about 50% to about 70% of a source of starch based flour comprising a mixture of from about 75% to about 90% of a flour having a WAI of from about 7 to about 9 and from about 10% to about 25% of a flour or starch having a WAI of from about 4 to about 6; (2) at least about 3% hydrolyzed starch having a DE of from about 5 to about 30; (3) from about 0% to about 6% of an emulsifier; (4) from about 20% to about 40% added water; (5) from about 0% to about 6% fat or oil; and (6) from 0 to about 3% solute; (b) forming the dough into a sheet; (c) cutting snack pieces from the sheet; and (d) frying said snack pieces in a fat or oil.
 2. The process of claim 1 wherein the dough is formed into a sheet having a thickness of from about 0.015 to about 0.035 inches (from about 0.038 cm to about 0.088 cm).
 3. The process of claim 2 wherein said hydrolyzed starch is selected from the group of maltodextrin and corn syrup solids.
 4. The process of claim 3 wherein said source of starch based flour is selected from the group consisting of potato flakes, potato granules and mixtures thereof.
 5. The process of claim 4 wherein said dough contains from 1% to about 3% of said emulsifier.
 6. The process of claim 5 wherein the dough comprises at least about 25% to 35% of said added water.
 7. The process of claim 6 wherein the dough comprises from about 55% to about 65% of said flour.
 8. The process of claim 7 wherein the dough contains from about 0.5% to about 2% of said solute.
 9. The process of claim 8 wherein said solute is sugar or salt.
 10. The process of claim 9 wherein the dough comprises from about 1% to about 4% of a fat comprising polyol fatty acid polyester having at least four fatty acid ester groups.
 11. The process of claim 10 wherein the emulsifier is a polyglycerol monoester.
 12. The process of claim 11 wherein the dough is fried in a polyol fatty acid polyester.
 13. The process of claim 11 wherein said dough comprises fat selected from the group consisting of triglycerides, reduced calorie fats and mixtures thereof.
 14. A process according to claim 1 comprising the additional step of spraying from about 1% to about 20% oil on the fried snack pieces wherein said oil has an iodine value of at least
 75. 15. A process according to claim 1 wherein the step of forming the dough into the sheet comprises milling the dough between mill rolls which are heated to a temperature of from about 90° F. to about 135° F.
 16. The snack pieces made by the process of claim
 1. 17. Fried snack pieces having from about 0.5% to about 4% water and from about 20% to about 38% nondigestible fat made from a dough comprising:(1) from about 50% to about 70% of a source of starch based flour comprising a mixture of for about 75% to about 90% of a flour having a WAI of from about 7 to about 9 and from about 10% to about 25% of a flour or starch having a WAI of from about 4 to about 6; (2) at least about 3% hydrolyzed starches having a DE of from about 5 to about 30; (3) from about 0% to about 6% of an emulsifier; (4) from about 20% to about 40% added water; (5) from about 1% to about 4% of a fat selected from the group consisting of triglycerides, reduced calorie fat, polyol fatty acid polyester and mixtures thereof; and (6) from about 0.5% to about 2% solute.
 18. The snack pieces of claim 17 wherein the fat is a sucrose fatty acid polyester having at least four fatty acid groups.
 19. The snack pieces of claim 18 wherein said snack has a nondigestible fat content of from about 23% to about 32%.
 20. The snack pieces of claim 17 wherein said emulsifier is a mixture of monoesters of hexapolyglycerol and stearic and palmitic acids. 